Soluble oil



Patented July 10, 1934 UNITED STATES PATENT OFFICE SOLUBLE on.

. No Drawing. Application March 4, 1932,

Serial No. 596,900

16 Claims. (Cl. 252-6) This invention relates to the production of the so-called soluble oils which disperse readily when added to water. These soluble oils may be used as wool oils with or without the addition of Water, or for the preparation of aqueous emulsions for use as sprays, dips, and as lubricants for use in the cutting and turning of metals.

In producing these soluble oils, an oil which is commonly of mineral origin and a soap are em- 10 ployed in conjunction with two or more common solvents or blending agents. Sodium corn oil soap or other soap of the same type may be employed as the soap required, and while the present invention is not limited to the use of sodium corn oil soap it is especially adapted thereto. 4

An object of the invention is to employ two or more common solvents or blending agents which shall possess better blending power for the soap and oil than has been known heretofore.

Another object is to produce economically a soluble oil having unique emulsification and stability properties.

A further object is to make a soluble oil in which a soap is used which does not tend to separate from the mixture as readily as other soaps generally employed and which does not impart any objectionable odor to the soluble oil.

The common solvents or blending agents, in a preferred form, should be particularly suitable for employment with an alkali metal corn oil soap such as sodium corn oil soap. We have found that if two or more common solvents are employed to increase the solubilities of the min- 35 eral 011 and the soap, the stability ofthe soluble oil and of the emulsions of the soluble oil, which form when theoil is mixed with water, is remarkably increased. This is particularly true when the -common solvent is a blend'of a dihydroxy alco hol such as ethylene glycol, propylene glycol, or diethylene glycol or a polyhydroxy alcohol such as glycerol and a monoalkylated dihydroxy alcohol like carbitol, (monoethyl ether of diethylene glycol) or a high boiling monohydroxy alcohol (like butyl alcohol or cyclohexanol). Materials such as the monoethyl ether of diethylene glycol are known to be particularly elfective as blending agents since the presence of the hydroxyl group tends to increase the solubility in water, and oi the ether group to increase the solubility in oil at the same time. A compound of this character has high solvent power for the soap. Such ethers of polyhydroxyl alcohols may be monoether derivatives of ethylene glycol or diethylene glycol, 55 or otherwise stated may be any ether derivati e of a polyhydroxyl alcohol which derivative contains at least one free hydroxyl group and which possesses the required solubility.

For convenience; we shall refer to the dihydroxy compounds as dialcohols and the monoalkylated derivatives thereof as alcohol-ethers.

The use of the blend of the two types of hydroxy compounds rather than one or the other of the materials alone, permits the manufacture of a clear soluble oil which will not become covered with a film or scum at normal temperatures. It was observed that soluble oils prepared with carbitcl alone were clear, but had a tendency to become coated with a film of insoluble material on their surface when exposed to air, and that soluble oils prepared with diethylene glycol alone did not :cum, but the resulting products were not entirely clear due to the presence of some insoluble material in suspension.

The carbitol possesses unique solvent properties in that a small amount of it imparts a clarity to the oil madewithdiethylene glycol by dissolving the insoluble material that such an oil mixture contains. The use of the two blending agents, carbitol and diethylene glycol, produces a soluble oil which will not scum when exposed to air and which is perfectly clear and homogeneous. The dialcohol and the ether-alcohol or high boiling monohydroxy alcohol have low vapor pressures and, therefore, do not evaporate readily from the oil. These are important characteris tics because the vaporization of either or both would cause the separation of' the ingredients of the miscible oil and the oil would not emulsify with water.

Thus the invention in a broad aspect resides in the preparation of a soluble oil from an animal, vegetable or mineral oil and sodium corn oil soap or other similar soap by the use of two or more I common solvents or blending agents which act as common solvents for both the oil and soap. In a preferred form one of these blending agents is eitheran ether derivative of a polyhydroxyl alcohol, which derivative contains a free hydroxyl group and possesses the solvent properties stated, or a high boiling monohydroxyl alcohol. The other blending agent which we propose to use is a dihydroxy alcohol like ethylene glycol, diethylene glycol or other glycols such as propylene glycol.

Considering the invention in greater detail, the soluble oil is produced by saponifying the corn oil with caustic solution by methods well known in the art and by promoting the solution of the soap in the oil by the addition of two or more though common solvents which act as blending agents. The soap may be sodium corn oil soap or other alkali metal soap; these soaps, as is well known, all being soluble in water. Sodium corn oil soap is particularly effective. The oil may be of animal, vegetable or mineral origin, and the solvents are a dialcohol blended with an ether-alcohol or a high boiling monohydroxyl alcohol which are capable of bringing the soap into a true or nearly true solution in the oil while cold, as distinguished from a colloidal solution or a colloidal jelly. The blending agents are common solvents for water, oil and the soap. As indicated above, we have found that while the soap may have a tendency to separate from the soluble oil if only one of the blending agents is employed, there is a remarkable increase in the stability and emulsi-- fication properties of the soluble oil when both types of blending agents are used in the same soluble oil.

We have also discovered that the addition of rosin to a soluble oil containing these blending agents imparts desirable emulsification properties to the oil and increases the stability of the oil.

As a specific example, a soluble oil composed of the following ingredients has unique emulsification and stability properties:

Percent Sodium corn oil soap 14 Water 6 Mineral oil 64 Water white rosin 10 Carbitol (monoethyl ether of diethylene glycol) Diethylene glycol 4 This oil is clear and will not become cloudy when cooled to a temperature of 60 F. and will not become covered with a film after standing exposed to the air at'a temperature of F. over a long period of time or at a temperature of 200 F. for one day. This oil will readily emulsify with water after standing exposed to the air at 200 F. for two days. Aqueous emulsions containing this oil are very stable even at a temperature of 200 F. In general, stable aqueous emulsions are prepared by using 1% to 35% of this oil, al-

stable aqueous emulsions can be prepared by using proportions of the oil outside these limits.

Many variations of the above formula may be made while operating according to our invention. For instance, the amounts of corn oil soap may vary appreciably, as from 8% to 16%. The percentages of common solvent, rosin, oil and water may vary within wide limits to produce a satisfactory miscible oil. Merely for purposes of exfor example, oils with viscosities of 70 to 260 seconds Saybolt Universal at 100 F. may be used. Animal or vegetable oil may be used together with or in place of the mineral oil.

It is to be understood that the above disclosures are not to be considered as limiting but merely as illustrative of the generic invention and that many variations may be made within the scope of the claims.

We claim:

1. A soluble oil comprising an oil, corn oil soap, carbitol and rosin.

2.'A soluble oil comprising an oil, an alkali metal soap, a dihydroxy alcohol and another common solvent for said oil and soap of the class consisting of an alcohol-ether and a high-boiling monohydroxy alcohol.

3. A soluble oil comprising a mineral oil, an alkali metal soap, a dihydroxy alcohol and another common solvent for said oil and soap of the class consisting of an alcohol-ether and a highboiling monohydroxy alcohol.

4. A soluble oil comprising an oil, sodium corn oil soap, 2. dihydroxy alcohol and another common solvent for said oil and soap of the class consisting of an alcohol-ether and a high-boiling monohydroxy alcohol.

5. A soluble oil comprising an oil, an alkali metal soap, a dihydroxy alcohol andan alcoholether.

6. A soluble oil comprising an oil, an alkali metal soap, a polyhydroxy alcohol and an alcoholether.

'7. A soluble oil comprising an oil, an alkali metal soap, ethylene glycol and an alcohol-ether.

8. A soluble oil comprising an oil, an alkali metal soap, ethylene glycol and carbitol.

9. A soluble oil comprising an oil, an alkali metal soap, a dihydroxy alcohol and a high boiling monohydroxy alcohol.

10. A soluble oil comprising an oil, a soap, a dihydroxy alcohol and butyl alcohol.

11. A soluble oil comprising an oil, a soap, ethylene glycol and butyl alcohol.

12. A soluble oil comprising an oil, a soap, a

dihydroxy alcohol and cyclohexanol.

13. A soluble oil comprising an oil, a soap, ethylene glycol and cyclohexanol.

14. A soluble oil comprising an oil, a soap, a dihydroxy alcohol and an alcohol-ether and rosin.

15. A soluble oil comprising an oil, sodium corn oil soap, rosin, carbitol and diethylene glycol.

16. A soluble oil comprising mineral oil 64%, sodium corn oil soap 14%, rosin 10%, carbitol 2%, diethylene glycol 4% and water 6%.

ARTHUR L. BLOUNT. DONALD W. BOARDMAN. 

